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Chemical Research in Chinese Universities 2003年第2期19卷 127-131页

作者： HANZheng-bo WANGXiu-li WANGLi WANGEn-bo LUANGuo-you HUNing-hai JIAHeng-qing DepartmentofChemistry NortheastNormalUniversityChangchun130024P.R.China ChangchunInstituteAppliedChemistry ChineseAcademyofSciencesChangchun130022P.R.China

A new compound, (C 6H 6N 3) 7(PMo Ⅵ 12 O 40 )(PMo ⅤMo Ⅵ 11 O 40 )·2CH 3CH 2OH·5H 2O, was synthesized and characterized by means of elemental analyses, IR spectroscopy, 1H NMR spect... 详细信息

A new compound, (C 6H 6N 3) 7(PMo Ⅵ 12 O 40 )(PMo ⅤMo Ⅵ 11 O 40 )·2CH 3CH 2OH·5H 2O, was synthesized and characterized by means of elemental analyses, IR spectroscopy, 1H NMR spectroscopy and single crystal \{X ray\} diffraction. This is the first example of benzotriazole polyoxometalates species. The compound crystallized in a triclinic space group P 1 with a =1 8378(4) nm, b =1 9078(4) nm, c =2 1037 (4) nm, α =\{63 41(3)°\}, β =64 31(3)°, γ =68 38(3)°, V =5 803(2) nm 3, Z =2, R 1=0 0486, wR 2=0 1357. The X ray crystallographic study showed that the crystal structure was constructed by electrostatic interactions and hydrogen bonds between dodecamolybdophosphorate anions and protonated benzotriazole cations. The electrochemical behavior and the reduction of nitrite and hydrogen peroxide electrocatalyzed by the title compound were studied.

关键词： Polyoxometalate Benzotriazole Synthesis Crystal structure Electrocatalysis

Distribution of primary school based on spatial network comprehensive model in low-income mountainous cities： a case study in Wanyuan, China

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Journal of Mountain Science 2017年第10期14卷 2082-2096页

作者： YANG Pei-feng HE Ran HOU hai-bo Faciliity of Architectuure and Urban Planning Chongqing UniversiityChongqing 400045 China Key Laboratory of New Technology for Construction of Cities in Mountain Areea Chongqing University Chongqing400045 China Chongqing planning and design institute Chongqing University Chongqing 400020 China

Focusing on the peculiarities of urban construction resulting from specific mountain terrains, the purpose of this study is to find out a suitable method based on a Spatial Network Comprehensive Model(SNCM) to reasonably plan and distribute primary schools in low-income mountain cities. The construction principles and advantages of the SNCM method are proposed and the method tested in Wanyuan city of Qinba Mountain area(Southwest China) to verify its feasibility and optimization. Taking account of the mountain terrain and its influence on user behavior, we used the SNCM method to build a comprehensive model which integrates the road slope and the walking speed of pupils into the basic spatial model. The model is used to calculate a reasonable layout of the primary schools and to validate the rationale. The results show that the SNCM method can be effectively applied in low-income mountainous cities. It can not only improve the accessibility and service efficiency of primary schools using as little capital-investment as possible, but also help the city grow in an intensive and efficient way.

关键词： Spatial network comprehensive model Primary school distribution Mountainous terrain Low-income mountainous cities China

Development and application of an instrument for simulating wetting-drying cycles of expansive soils under loads

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Journal of Mountain Science 2018年第11期15卷 2552-2560页

作者： DONG Jun-gui LV hai-bo WU Wei School of Civil Engineering and Transportation South China University of Technology Guangzhou 510641 China College of Civil Engineering and Architecture Guilin University of Technology Guilin 541004 China

Alternating rainfall and evaporation in nature severely impact the shear strength of expansive soils. This study presents an instrument for simulating the effect of wetting–drying cycles on the strength of expansive soils under different loads, and its testing error is verified. With this instrument,direct shear tests were performed on samples experiencing 0-6 cycles under vertical loads of 0 kPa,5 kPa, 15 kPa, and 30 k Pa. The results found that this instrument provides a new method for evaluating the effects of wetting–drying cycles on soils, and this method represents actual engineering conditions more accurately than do preexisting methods. It accurately controls the water content within 1% while simulating the specified loads at different soil *** is significantly affected by wetting–drying cycles, while the friction angle is not as sensitive to these cycles. Decrease in shear strength can be attributed to the fissures in soils caused by wetting–drying cycles. The existence of vertical loads effectively restricts shrinkage fissuring and cohesion attenuation, consequently inhibiting the attenuation of shear strength.

关键词： Expansive soils Wetting-drying cycle Instrument Load Shear strength

Scaling out NUMA-Aware Applications with RDMA-Based Distributed Shared Memory

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Journal of Computer Science & Technology 2019年第1期34卷 94-112页

作者： Yang Hong Yang Zheng Fan Yang Bin-Yu Zang hai-Bing Guan hai-bo Chen Shanghai Key Laboratory for Scalable Computing Systems Shanghai Jiao Tong UniversityShanghai 200240China

The multicore evolution has stimulated renewed interests in scaling up applications on shared-memory multiprocessors,significantly improving the scalability of many *** the scalability is limited within a single node;therefore programmers still have to redesign applications to scale out over multiple *** paper revisits the design and implementation of distributed shared memory (DSM)as a way to scale out applications optimized for non-uniform memory access (NUMA)architecture over a well-connected *** paper presents MAGI,an efficient DSM system that provides a transparent shared address space with scalable performance on a cluster with fast network *** is unique in that it presents a NUMA abstraction to fully harness the multicore resources in each node through hierarchical synchronization and memory *** also exploits the memory access patterns of big-data applications and leverages a set of optimizations for remote direct memory access (RDMA)to reduce the number of page faults and the cost of the coherence *** has been implemented as a user-space library with pthread-compatible interfaces and can run existing multithreaded applications with minimized *** deployed MAGI over an 8-node RDMA-enabled *** evaluation shows that MAGI achieves up to 9.25:4 speedup compared with an unoptimized implementation,leading to a sealable performance for large-scale data-intensive applications.

关键词： distributed shared memory (DSM) scalability multieore evolution non-uniform memory access (NUMA) remote direct memory access (RDMA)

Query Acceleration of Graph Databases by ID Caching Technology

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Journal of Electronic Science and Technology 2019年第1期17卷 41-50页

作者： Wei Jiang hai-bo Hu Liu-Gen Xu the School of Information and Software Engineering University of Electronic Science and Technology of China

In this paper, we approach the design of ID caching technology(IDCT) for graph databases, with the purpose of accelerating the queries on graph database data and avoiding redundant graph database query operations which will consume great computer resources. Traditional graph database caching technology(GDCT)needs a large memory to store data and has the problems of serious data consistency and low cache utilization. To address these issues, in the paper we propose a new technology which focuses on ID allocation mechanism and high-speed queries of ID on graph databases. Specifically, ID of the query result is cached in memory and data consistency is achieved through the real-time synchronization and cache memory adaptation. In addition, we set up complex queries and simple queries to satisfy all query requirements and design a mechanism of cache replacement based on query action time, query times, and memory capacity, thus improving the performance *** experiments show the superiority of our techniques compared with the traditional query approach of graph databases.

关键词： Cache graph database query efficiency

CBSC: A Crowdsensing System for Automatic Calibrating of Barometers

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Journal of Computer Science & Technology 2019年第5期34卷 1007-1019页

作者： hai-bo Ye Xuan-Song Li Li Sheng Kai Dong College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211100China School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China School of Computer Science and Engineering Southeast UniversityNanjing 211189China

The mobile crowdsensing software systems can complete large-scale and complex sensing tasks with the help of the collective intelligence from large numbers of ordinary users. In this paper, we build a typical crowdsensing system, which can efficiently calibrate large numbers of smartphone barometer sensors. The barometer sensor now becomes a very common sensor on smartphones. It is very useful in many applications, such as positioning, environment sensing and activity detection. Unfortunately, most smartphone barometers today are not accurate enough, and it is rather challenging to efficiently calibrate a large number of smartphone barometers. Here, we try to achieve this goal by designing a crowdsensingbased smartphone calibration system, which is called CBSC. It makes use of low-power barometers on smartphones and needs few reference points and little human assistant. We propose a hidden Markov model for peer-to-peer calibration, and calibrate all the barometers by solving a minimum dominating set problem. The field studies show that CBSC can get an accuracy of within 0.1 hPa in 84% cases. Compared with the traditional solutions, CBSC is more practical and the accuracy is satisfying. The experience gained when building this system can also help the development of other crowdsensing-based systems.

关键词： crowdsensing system smartphone sensing barometer calibration

Electrochemistry of Hydroquinone Derivatives at Metal and Iodine-modified Metal Electrodes

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Chemical Research in Chinese Universities 2006年第4期22卷 493-499页

作者： HOU Peng HAN Dong-xue NIU Li LIN hai-bo State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China Graduate School of the Chinese Academy of Sciences Beijing 100039 P. R. China College of Chemistry Jilin University Changchun 130021 P. R. China

The difference in the electrochemical behavior of hydroquinone and pyrocatechol at platinum and gold surfaces was analyzed using voltammetry and attenuated total reflection Fourier transform infrared spectroscopy. The results show that the hydroquinone derivatives are adsorbed on a gold surface with vertical orientation, which makes the electron transfer between the bulk species and the electrode surface easier than that in the case of flat adsorption of hydroquinone derivatives that occurs at a platinum electrode. The formation of the vertical conformation and the rapid process of electron transfer were also confirmed by quantum chemistry calculations. In addition, the pre-adsorbed iodine on the electrodes played a key role on the adsorbed configuration and electron transfer of redox species.

关键词： Hydroquinone derivatives Iodine-modified Electrochemistry

Penetration and internal blast behavior of reactive liner enhanced shaped charge against concrete space

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Defence Technology（防务技术） 2022年第6期18卷 952-962页

作者： Hao Zhang Yuan-feng Zheng Qing-bo Yu Chao Ge Cheng-hai Su hai-fu Wang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081PR China

Penetration and internal blast behavior of reactive liner enhanced shaped charge against concrete space were investigated through experiments and *** volume of the enclosed concrete space is about 15 m^(3).The reactive liner enhanced shaped charge utilizes reactive copper double-layered liner,which is composed of an inner copper liner and an outer reactive liner,while the reactive material liner is fabricated by PTFE/Al(Polytetrafluoroethylene/Aluminum)powders through cold-pressing and *** explosion experiments show that,compared with the shaped charge which utilizes copper liner,the penetration cavity diameter and spalling area of concrete by the novel shaped charge were enlarged to 2 times and 4 times,***,the following reactive material had blast effect and produced significant overpressure inside the concrete closed *** analysis indicates concrete strength and detonation pressure of reactive material both affect the penetration cavity *** the blast behavior of reactive material inside the concrete space,developing TNT equivalence model and simulated on AUTODYN-3 D for *** results reproduced propagation process of the shock wave in concrete space,and revealed multi-peaks phenomenon of overpressure-time ***,the empirical relationship between the peak overpressure and relative distance for the shock wave of reactive material was proposed.

关键词： Shaped charge Penetration Blast Concrete Numerical simulation

Structure and mechanical properties of Zr/TiAlN films prepared by plasma-enhanced magnetron sputtering

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Rare Metals 2015年第10期34卷 717-724页

作者： Guang Xian hai-bo Zhao Hong-Yuan Fan Hao Du School of Manufacture Science and Engineering Sichuan University The Analysis and Testing Centre Sichuan University

The purpose of this study was to investigate the effects of Zr interlayer on the structure and mechanical properties of TiAlN films, which were deposited on the M2 high-speed steel substrates by means of plasma-enhanced magnetron sputtering. The result shows that the crystal orientation of Zr/TiAlN films is similar to that of single-layered TiAlN films, but the difference is that AlN(111) of Zr/TiAlN films disappears completely. With respect to Zr interlayer, the texture coefficient of Zr/TiAlN films is approximately 1. Zr/TiAlN films exhibit a compact isometric structure, which is distinctly different from the columnar structure existing in the single-layered TiAlN films and Ti/TiAlN films. The hardness and H3/E*2 of Zr/TiAlN films are, respectively, enhanced to be 36.6 GPa and 0.147. With a few cracks emerging around the indention, the adhesion strength of TiAlN films is obviously advanced by adding Zr metal interlayer.

关键词： TiAlN films Structure Orientation Hardness Adhesio

Bioleaching of vanadium from barren stone coal and its effect on the transition of vanadium speciation and mineral phase

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International Journal of Minerals,Metallurgy and Materials 2018年第3期25卷 253-261页

作者： Xin Wang hai Lin Ying-bo Dong Gan-yu Li School of Civil and Resource Engineering University of Science and Technology Beijing Beijing 100083 China School of Energy and Environmental Engineering University of Science and Technology Beijing Beijing 100083 China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083 China

This study determined the optimal conditions required to obtain maximum vanadium extraction and examined the transition of mineral phases and vanadium speciation during the bioleaching process. Parameters including the initial p H value, initial Fe^(2+) concentration, solid load, and inoculum quantity were examined. The results revealed that 48.92 wt% of the vanadium was extracted through bioleaching under optimal conditions. Comparatively, the chemical leaching yield(H_2SO_4, pH 2.0) showed a slower and milder increase in vanadium yield. The vanadium bioleaching yield was 35.11 wt% greater than the chemical leaching yield. The Community Bureau of Reference(BCR) sequential extraction results revealed that 88.62 wt% of vanadium existed in the residual fraction. The bacteria substantially changed the distribution of the vanadium speciation during the leaching process, and the residual fraction decreased to 48.44 wt%. The X-ray diffraction(XRD) and Fourier transform infrared(FTIR) results provided evidence that the crystal lattice structure of muscovite was destroyed by the bacteria.

关键词： bioleaching stone coal BCR-sequential extraction vanadium speciation mineral phase